Giant Cell Arteritis and PET Scan (GAPS) Study

Giant Cell Arteritis and PET Scan (GAPS) Study - Improving the Diagnosis and Prognostication of Giant Cell Arteritis Through the Novel Use of Positron Emission Tomography and Immune Biomarkers

Giant cell arteritis (GCA) is a medium to large vessel vasculitis with a predilection for the superficial cranial and intrathoracic arteries. Diagnosing the condition and predicting which patients will develop large vessel complications remains a challenge. There are limitations with temporal artery biopsy, magnetic resonance angiography and ultrasound of temporal arteries and American College of Rheumatology classification criteria.

Positron emission tomography (PET) has been shown to be a useful modality in detecting inflammation in large intra-thoracic vessels but previously has not been able to accurately detect FDG uptake in the superficial cranial arteries due to poor spatial resolution. Newer scanners can perform finer cuts of the head and can detect uptake in these arteries.

This study has three main components:

1. Cross sectional study assessing the accuracy of PET uptake in the superficial cranial and intrathoracic arteries of suspected GCA patients for the diagnosis of GCA
2. Cohort study assessing the prognostic implication of FDG aortic uptake on aortic diameter at 24 months
3. Cohort study assessing the Th1 and Th17 cytokine profile in patients with and without FDG PET uptake at 0, 6 and 24 months

Study Overview

• Status: Completed
• Conditions: Giant Cell Arteritis

• Study Type: Observational
• Enrollment (Actual): 64

Contacts and Locations

Study Locations

• Australia
  • New South Wales
    • St Leonards, New South Wales, Australia, 2065
      • Royal North Shore Hospital

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 50 years and older (ADULT, OLDER_ADULT)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: All

• Sampling Method: Probability Sample

Study Population

Suspected GCA

Description

Inclusion Criteria:

• Rheumatologist, neurologist or ophthalmologist suspect diagnosis of GCA
• Age > 50

• Meet at least 2 of 1990 American College of Rheumatology classification criteria for GCA

  1. Age >= 50
  2. ESR >= 50
  3. New onset localised headache
  4. Temporal artery abnormality (tenderness or decreased pulsation)
  5. Positive biopsy (will not be available at time of enrolment)

Exclusion Criteria:

• Corticosteroid therapy for > 72 hours before first PET scan
• Prolonged corticosteroid therapy (> 1 week) for another indication in past 6 months
• History of vasculitis or connective tissue disease
• Active malignancy

Study Plan

How is the study designed?

Number of groups / cohorts

2

Cohorts and Interventions

Group / Cohort
Suspected GCA (GCA final diagnosis)
Suspected GCA (alternative final diagnosis)

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Time Frame
Diagnostic accuracy of FDG uptake in the superficial cranial or intrathoracic arteries for the diagnosis of temporal artery biopsy proven GCA amongst patients with suspected GCA	Baseline

Secondary Outcome Measures

Outcome Measure	Time Frame
Difference in aortic diameter at 24 months between patients with and without PET scan aortic uptake at time 0.	24 months
Difference in Th1 and Th17 axis cytokines in patients with and without thoracic large vessel PET uptake at 0, 6 and 24 months	24 months
Prevalence of varicella zoster virus antigen and DNA in temporal artery biopsy GCA specimens	24 months
Prevalence of acute varicella zoster IgM serology positivity in biopsy confirmed GCA patients	24 months
Difference in combined vascular events between GCA patients with and without thoracic large vessel PET uptake at 0, 6 and 24 months	24 months
Difference in temporal artery histology between GCA patients with and without thoracic large vessel PET uptake at 0 months	Baseline
Difference in temporal artery histology between GCA patients with and without temporal artery PET uptake at 0 months	Baseline

Collaborators and Investigators

• Sponsor: Royal North Shore Hospital
• Investigators: Principal Investigator: Anthony M Sammel, MBBS, Royal North Shore Hospital, St Leonards, Australia

Publications and helpful links

General Publications

• Sammel AM, Hsiao E, Schembri G, Nguyen K, Brewer J, Schrieber L, Janssen B, Youssef P, Fraser CL, Bailey E, Bailey DL, Roach P, Laurent R. Diagnostic Accuracy of Positron Emission Tomography/Computed Tomography of the Head, Neck, and Chest for Giant Cell Arteritis: A Prospective, Double-Blind, Cross-Sectional Study. Arthritis Rheumatol. 2019 Aug;71(8):1319-1328. doi: 10.1002/art.40864. Epub 2019 Jun 12.

Study record dates

Study Major Dates

• Study Start (ACTUAL): May 15, 2016
• Primary Completion (ACTUAL): January 28, 2020
• Study Completion (ACTUAL): January 28, 2020

Study Registration Dates

• First Submitted: May 9, 2016
• First Submitted That Met QC Criteria: May 11, 2016
• First Posted (ESTIMATE): May 13, 2016

Study Record Updates

• Last Update Posted (ACTUAL): March 12, 2020
• Last Update Submitted That Met QC Criteria: March 10, 2020
• Last Verified: March 1, 2020

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Cardiovascular Diseases; Vascular Diseases; Cerebrovascular Disorders; Brain Diseases; Central Nervous System Diseases; Nervous System Diseases; Skin Diseases; Immune System Diseases; Autoimmune Diseases of the Nervous System; Autoimmune Diseases; Musculoskeletal Diseases; Rheumatic Diseases; Connective Tissue Diseases; Muscular Diseases; Vasculitis; Skin Diseases, Vascular; Vasculitis, Central Nervous System; Polymyalgia Rheumatica; Giant Cell Arteritis; Arteritis
• Other Study ID Numbers: RESP/16/44

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO